Marine aircraft



E. A. sPERRY MARINE AIRCRAFT Aug. 16, 1932.

Filed Nov. 20, 1929 2 Sheets-Sheet l W Rm Y. O E TO! M jm M N m m.

16, 1932- E. A. SPERRY 1,871,476

MARINE AIRCRAFT Fild Nov. 20, 1929 2 Sheets-Sheet 2- repetitions of this sort Patented Aug. 16, 1932 ELMER A. SPERRY, or BROOKLYN, NEW

YORK; 'AssrGNoR TO srnnmr DEVELOPMENT COMPANY, on DOVER, DELAWARE, A GORPClRATION' OF DELAWARE,

MARINE [AIRCRAFT Application filed November 20,1929. Serial No. 408,459.

This invention relates to marine aircraft which are characterized by Wings and afloating portion, such as a housing or cabin for the pilot and for passengers or freight; In the case of all such craft it is desirable that the water-borne part be as small and narrow and as completely stream-lined as possible. This, however, results in a definite instability when the craft is floating on water. In the case of. a monoplane type of aircraft, it is perfectly evident that When such a machine stands on the ground and a side gust comes and lifts one of the wings, the other wing will be correspondingly depressed or tilted until it touches the ground, whereupon no further motion will take place and it now stands in position to oppose very high velocity, lateral gusts, and wind pressures under the windward wing without upsetting" or turning over and thus the plane will suffer no damage therefrom. boats, however, it is entirely different. If a wind should lift one of the Wings, the smallness and narrowness, as well as the streamline formation of the housing, makes it easy for the wind to tilt the craft. When the lee wing in the course of its depression or tilting touches the water it encounters only the normal buoyancy of the rather nar rou tip and hence meets no substantial resistance. It has been found on numerous of accident that the wing, and even a large winged float, will keep on dipping deeper and deeper into the water, since the windward wing, as it tilts upwardly, offers a more direct surface to the wind which, therefore, becomes increasingly effective. As a result, the entire plane turns like a windmill until it lies 011 its back, suffering very serious damage directly and indirectly and injurying also passengers and cargo.

The principal object of the present invention is to overcome this serious difliculty and still retain the ideal ship-shape of the flying boat and also to eliminate wing float appendage. t may here be stated'that in order to overcome the difiiculties hereinbefore mentioned, doublepontoons arranged side by side but at considerable distances aparthave been In the case of flying employed. This construction has been found to ofler a great deal, more head resistance, thus lowering the flying etficiency of the structure as a whole, but even of greater importanceis the fact that it did not overcome the difliculty because planes equipped with such double pontoon structures have also been overturned when caught by sudden side gusts, owing to the fact that such planes can be maneuvered on the water only very slowly. Tokeep the flying efliciency high and at the same time, to safe-guard against the class of accident described, I provide novel means for yielding a dependable extra buoyancy near the tip of the wing without in anywa interfering with practically perfect flight efli-. ciency when in the air. I disclose in the "following specification two forms for 'accom. plishing this result, the first, being in the form ofa perfect winged form enlargement of perfect stream line form but of a thicker Wing structure which may also be wider both fore and aft to secure proper buoyancy and proper location of the center This form is completely moisture proof and watertight. In a second form of the in? vention, I provide concealed inflatable floats adapted to beinflated upon engagement of the tip of a wing with the water. These floats are normally concealed within cavities in the wing structure so as not to interfere in the sl ghtest with, the head resistance or high efficiency of the plane in flight.

of, buoyancy.

Further objects and advantages of my in-l vention will become apparent in the following detailed description thereof. In the accompanying drawings, H c

Fig. 1 is a front view of an amphibian plane illustrating diagrammatically the necessity for my invention.

Fig. 2 is an assembly viewof the releasing mechanism for controlling the supply of gas under pressure for inflating the floats.

Fig. 3 is a vertical section through the water soluble element for controlling the float inflatingmechanism. I I 7 Fig. 4 is a detailed'view of the mechanismshown in Fig. 3 for enabling the water solu= ble member to be operated by hand so that relatively unstable,

. the floats disclosed in the inflation mechanism may be placed under the control of a pilot.

Fig. 5 is an end view of a Wing tip, showing one of the floats extruded together with means for limiting the side expansion of sald float.

Fig. 6 is a vertical section through a wing,

showing the floats packed within the stream- V -ly light and strong gas-tight envelopes or lines of said wing structure. a

Fig. 7 is a view similar to Fig. 6 but showing the floatsin extruded position.

Fig. 8 1s a vertical section through another portion of the wing and showing the mechanism for controlling the supply of inflating Fig. 9 is an enlarged detail of the means for controlling the release element of the mechanism for limiting the side expansion of the floats. V r

Fig. 10 is a plan View, largely diagrammatic, showing the means for controlling automatically and by hand the supply of gas under pressure for inflating the floats. .4 I

Fig. 11 is a front elevation of the spring mechanism for rendering effective the means for limiting the side expansion of the float.

Fig. 12 is a view illustrating the modified form of my invention wherein an enlarged wing tipstructure is employed rather than Figs. 6 and 7.

Fig. 13 is a perspective of a modified form of my invention. f i

The reason for'this invention is shown in Fig. 1, which discloses an amphibian monoplane having Wings W and a very narrow, housing or cabin H If a wind gust, as indicated by the arrow, should catch under one wing, the plane would readily be tilted from the full line position '1 to the dotted line position 2, where a portion of the wing tip on the lee side would tip into the water. The. only resistance it would meet would be the slight buoyancy of the relatively narrow wing tip which would ofler little resistance. As the windward wing reaches the position 2 it offers a more direct face to the wind which then becomes increasingly effective to tilt the plane to the posltions 3 and 4 and finally completely overturns the craft.

Referring now first to Fig. 12, this illustrates the simplest'form of my invention and comprises a water-tight enlarged wing section 10 at the extreme end of wing W, which is not only thicker than the wing at that point but may also be wider and longer to secure proper buoyancy and location of the center of buoyancy. Such a water-tight enlarged wing section will yield a buoyancy of between one and three tons, as required, while its air-foil form corresponds to the form of the rest of the wing structure W and gives a very low; head resistance. This construc tion is very simple and entirely adequate for the purpose of overcoming the difliculties floats within its respective cavity 13 to fulfill the same function by means normally hidden in the wing structure except at the time when its special function is desired.

This means may take the form of extremefloats 13 which are closely folded and packed away inside of suitable cavities 13 within the wing structure. I may store each of these through an opening or aperture 14 in the bottom of the wing. 'Thefloats may be attached to the rim of the respective opening 14 so that when the floats are extruded they will be connected to the wing around the periphery of said apertures or openings 14. When packed within the wing, opening 14 may be closed by means of a plate 15 firmly held in position by a'friction joint so that when the bags areinflated, the plates 15 will be blown off and the bags extruded through apertures 14. The plates 15 are preferably fixed to the bags themselves at one side thereof so that when the bags are in flated the plates will remain attached thereto as'shown in Fig. 7 7 Anchor straps 18 may be provided for limiting the expansibility of the bags and for assisting to maintain the same in attachment to the peripheries of apertures 14.

In an alternative form shown in Fig. 13, the'folded floats may be carried upon a sin-- gle plate forming the bottom of the wing structure, the said plate being, provided with the apertures 14 as before so that after the floats have been in use a new plate 14 with a new set of folded floats may, easily be ate means for inflating the floats quickly with a gas under pressure as soon as the necessity therefor arises, that is to say, as soon asone wing tip or the other engages and is submerged beneath the surface of the water. For this purpose I may provide a tank 20 filled with gas under suitable pressure to inflate the gas bags with the necessary rapidity to extrude the same through apertures 14. The supply of gas may be controlled by a valve 22 which is designed to be operated automatically when a wing tip dips beneath the water, or by hand at the will of an operator. The means for accomplishing this automatically may take the form of a spring-wound shaft 23 to which is attached a spring 24 normally tending to rotate the same in such direction as to move an arm 25 in a given dias shown in Fig. 6, each v or withdrawal of the soluble block,

rection, suclras for instance, thatv indicated bythe arrow 26. The movement oi? said arm in. thedinection of arrow 26 would windv a cable 27. upon a pulley 28 to operate the; valve 22 and supply gas through the channels 39 to the respective, floats. 'llhe 1110Veinent ofl arm 25in thesaid; efieotive direction; isnorm-ally retarded by means such as a block 32 whichis readilysoluble in waterand normally of a hard crystallinestructure con.- tained within a tub6;33; having a cut-away portion BLthroughwhich arm- 25 would be able, to operate were it not for the intervention ot the hard,.-crystalline, water-soluble block. The said. block, as shown in Fig. 8;,

is located at the extreme wing tip and has an open: lower end: which; may be covered by a; filter 36, which permits the water to. pass therein: and upwardly into engagement with; theblock 32 to dissolvethe, same as soon as the; tip dips beneath the surface of the water- Upon; dissolution. of the water-soluble block arm 25$ is free; to rotate; under the influence; of spring 24: to open the valve 22 and supply the floats with gas under pressure as heretotore described. As soon as the block- 32 is dissolyed, the valve 37 within tube 33,, normally held open by engagement with the block 32, isv closed by a spring 38, so that no watercan-enter within; the wing structure. A meansgis; also provided whereby the pilot, may release the block: 32. at will- For this purpose, said block is shown as provided witlt an overhanging top 40 around which "T.- engages a fork 41 forming one arm of a bell crank 42, the other arm of which has connected thereto means such as a cable 4-8 under the control of the pilot in the cabin or housing. When drawing upon cable 43, the

pilot will mechanically release the block 32 to cause arm 25 to open valve 22 and hence extrude the floats.

I may provide means for limiting the sidewise movement of the floats and also provide 12411821118 for rendering said limiting means effective only when the floats are inflated, so that normally such limiting means also lies flush within the wing structure so as to offer no head resistance thereto. Such. limiting "3 means is disclosed in Figs. 5, 7, 9, 10 and 11 at 50. Each of said limiting means as disclosed in Fig. 9, comprises a toggle joint, the two parts 51 and 52 of which are pivoted at 53 and said joint being adapted to bend '31, downwardly when in effective position. The

said. downward bending movement at joint is normally prevented by means of a pin 54 engaging beneath a ledge 55 carried by one of the members of the toggle. When arm 25 is set free to rotate by the dissolution a pulley (see Figs. 8 and 10) rotates therewith to draw upon cables 61 and 62 which extend over suitable pulleys to the outer end 65 of ipin 54. This withdraws pin 54 and leaves the toggle 531,, 5.2;. 53. comprising the; limiting; member 5'0'treet0. bend downwardly tutorinthe} limiting means as shown in Figs. 5. and 7.. In order to: eflecttbis. downward move,-

ment of the; toggle as soon; as pin 54% is withdrawn from' bone ath; ledge 55,;I n1ay provide and 62, are wound up, pulley 60 first withdraws pin. 54. and then, after spring 7.0 and rod 7.1-. have bent joint 5,3, downrwandly, said. cable pullsar-In 7.5: inwardly in. av slot 76- (see Fig, 5:) to eflect the said downward move ment of thej'ointancl the flexing oftheatoggl 7 member;

In. accordance with. the provisions of the:

patent statutes, I have herein. described. the

principle and. operation 013 my invention, to.-

gether with. the apparatus which. I, now con;-

Z0. androd/ZL are-however ineffective downwardly as long as; pin

55. Whom.

slder to: representthebest embodimentthereoflbut I desireto have it understood thatthe apparatusshown is only illustrative and that the invention. can be carried out: by other means. Also, wlnle it is designed. touse the.

variousteatures and elements in the combi--' nation and relations described, some of, these may be altered and others omitted without interfering with the, more general results outlined; and the invention extends to such. use...

Having described. my invention,. what I claim and desire to secure by is ing wing,

Letters Patent,

1.. Ina. marine aircraft, a laterally extend. a. (lBVICQ fO I: maternally auginentmg the buoyancy oi saidwing at or near said.

lio

t p, soorgani'zedi, as to. preserve a contour best suited for flight sai d5 devicebeing normally inefiectiye and meansv responsive to. the. engagementofsaid. wingwith the water where by said: device may be, rendered effective.

ing wing; in. inflatable devicefor materially augmenting the buoyancy of sa1d.wing,;said

wing having av cavity in which said deviceis carried. when. ineffective so asv to preserve the:

wing contour, best suited for flight, and means responsiveto engagement of said} wing: with the: water for extrudingsaid device fI'OIIliSflld cawityand? inflating the same.v

In; a. marine aircraft, a laterally extend-- 11 1-. a marine aircratt, a. laterally extends 7 ing; wing a plurality 0t, inflatable devices; for

materially augmenting thebnoyancy of said 13%]; p

wing, said wing having a plurality of cavities in which said devices are carried when ineffective so as to preserve the wing contour best suited for flight, and means responsive to engagement of said wing with'the water said bag, and means responsiveto engage-- ment of said wing with the water for controlling said connection.

5. In a marine aircraft, a collapsible gas bag so disposed on said craft in collapsed condition as to preserve the minimum flightre sistance of the craft, a source of fluid pres sure, a' connection between said source and said bag, means responsive to engagement of said wing with the water forcontrollingsaid connection, and hand-operated means fora-lternatively controlling said connection.

6., In a marine aircraft, a collapsible gas bag so disposed on said craft in collapsed condition as to preserve the minimum flight resistance of the craft, a source of fluid pressure,

a connection between said source and said bag, and automatic means for controlling said connection in response'to engagement of a predeterminedpart of said craft with the water, said automatic meansincluding asservo motor for operating said connection and a water soluble element, in said part and normally rendering said servo motor lneflectlve' but adapted to dissolve on engagement with the water to permit operation of said servo motor. -I p p 7. In a marlne alrcraft, a collapsible gas bag so disposed on said craft in colla sed condition as to preserve the minimum ight resistance of the craft, a source of fluid pressure, a connection between sald source and said bag, automatic means for controlling said connectionin response to engagement of a predetermined part of said craft with the water, said automatic means including a servo motor for operating said connection and a water soluble elementin said part and normally rendering said servo motor ineffective but adapted to dissolve on engagement with Y the water to permit operation of said servo motor, and hand-operated means whereby saidwater soluble element may be withdrawn.

8.'In a marine aircraft, a collapsible gas bag so disposed on said craft in collapsed condition as to preservethe minimum flight resistance of the craft, a source of fluid pressure, a controllable connection between said source and said bag, means for limiting the lateral expansibility of the said inflated bag,

and means for operating said connection to v inflate said bag and slmultaneously render said limiting means eflect-ive.

senate 9.- In a inarine' aircraft, a wing, a collap= sible gas bag so disposed on said craft in collapsed condition as to preserve the minimum flight resistance of the craft, a source of fluid pressure, a connection between said source and said bag, and means responsive to engagement of said wing with the water for controlling said connection, said means including a servo motor for operating said connec- I tion and means whereby said servo motor operates said l1m1t1ng means.

- 10. Inamarine aircraft, a collapsible gas bag so disposed on said craft-in collapsed condition as to preserve the minimum flight resistance of the craft, a source of fluid pressure, "a connection between said source and said bag,and automatic means for controlling said connection in responseto engagement of a predetermined part ofsaid craft with the water, said automatic means including a tube having anppen end adapted to engage the water and permit the same to pass therein, a

water soluble element carried by said tube,

signature. c

' ELMER A. SPERRY. 

